I totally agree with the above comments. I use to own a 555 and I drove a 4 ohm load.
Adcom 555,B&k St 140, Mccormack .5 dna
Out of these older "vintage" amps...which one would mate best with a 4 ohm load? ALso...which one would sound competitive with modern amps in terms of transparency,detail, and bass reproduction? ANd if you were to add a tube pre...which one would you choose?